General Overview Of Gait Disorders
Gait is the manner in which an individual walks. Gait disorders are thought to affect 10% of people between the ages of 60-69. However, this increases to 60% in individuals over the age of 80. This highlights the effect that aging can have upon gait in older adults. Gait disorders have been identified as one of the most consistent risk factors for falling in older adults. Gait speed is also a strong indicator of general health in older adults. There are two main phases of the gait cycle: the stance phase and the swing phase. The stance phase can be further divided into the heel strike, foot flat, midstance and heel off. Additionally, the swing phase can be divided into the toe off and midswing. Frequent measures of gait include walking speed, cadence and stride length. In a normal cycle, the stance phase accounts for 60% of the cycle, and the swing phase 40%. Abnormalities in gait are often recognizable due to deviation from this, either via increased swing or stance phase preference General Overview Of Gait Disorders
Electromyography research has identified that leg muscle groups such as the calves, gluteals, quadriceps and hamstrings, as well as muscles in the trunk such as the erector spinae and the abdominal muscles are heavily utilized within normal gait. For example, neuropathic gait is an abnormality whereby an individual shall exhibit a high stepping gait. This is due to the inability to dorsiflex the ankle joint within the swing phase. The muscles which work to dorsiflex the foot include the tibialis anterior, extensor hallucis longus, and the extensor digitorum longus. Sarcopenia may reduce the functionality of these muscles, causing neuropathic gait. Similarly, mypoathic gait is identifiable via circumduction of the leg within the swing phase, and is suggested to be caused by weakness in the proximal muscles of the pelvic girdle.
Neurological impairments can lead to gait disorders. Parkinson’s disease, a degenerative disorder of the central nervous system, can lead to sensory ataxia, which is the impairment of the ability to smoothly coordinate voluntary movements. It is suggested that impaired basal ganglia function leads to decreased motor control, causing slowed movements, resting tremor and postural instability. Parkinson’s disease is prevalent in 1% of the population over 60 and 20% of people over the age of 80 have Parkinsonism associated gait disturbances. Typical gait abnormalities include increased left-right gait asymmetry, leading to a lack of a steady gait rhythm. Increased stride variability and lack of steady gait rhythm are associated with an increased risk of falling.General Overview Of Gait Disorders
Another neurological impairment which can influence gait is stroke. Strokes are most often caused by a blood clot, blocking a blood vessel in the brain. This results in an area of the brain being deprived of oxygen, which can lead to the death of brain cells. There are more than 100,000 strokes every year in the UK, a large proportion of those being suffered by older adults. Stroke Association (2017) also cites that black people are twice as likely to suffer from a stroke as white people. Other stroke risk factors include old age, hypertension and being male.
Consequences of stroke include decreased muscular function, decreased control of voluntary movements and increased spasticity. Myopathic gait abnormalities can be a consequence of a stroke. Research suggests stroke can lead to unilateral weakness, in combination with increased spasticity of distal lower leg muscles such as the tibialis anterior, can lead to increased circumduction of the leg (i.e myopathic gait), due to the inability to adequately flex the knee joint throughout the swing phase.
Osteoarthritis of the hips and knees are common non-neurological causes of gait disorders in older adults. Osteoarthritis is the most common degenerative joint disease and a major cause of pain and disability in older adults. Osteoarthritis is the structural and functional failure of synovial joints, associated with a lack of cartilage. Subsequent impacts upon gait may include limited range of motion, avoidance of weight-bearing and asymmetry. Older adults with knee osteoarthritis have been found to exhibit differences within knee adduction moment, flexion moment and flexion angle in comparison to older adults without osteoarthritis. Similarly, osteoarthritis of the hip can lead to abnormalities in trunk movements, often to compensate for reduced hip extension. Whilst this research suggests that osteoarthritis can lead to gait abnormalities, Ng and Tan (2013) claim that these gait abnormalities may not lead to a significantly increased risk of falling. This provides opposition to research which has associated gait disorders with increased risk of falling.General Overview Of Gait Disorders
Research has explored the relationships between mobility and falls in elderly. Gait abnormalities such as myopathic gait, as well as the symptoms of osteoarthritis, are associated with reduced mobility. Older adults whom suffer more falls tend to exhibit reduced mobility in comparison to their peers, and severe mobility limitations have been suggested to increase risk of falling by up to 15 times. Furthermore, reduced mobility is associated with reduced quality of life in older adults, and increased depression. Whilst mobility encompasses a broad spectrum of movements, Dionyssiotis (2012) states that the age related decline in speed, endurance, and muscle function leads to difficulties in everyday tasks such as arising from a chair, or re-correcting ones stance following a slip, which can lead to increased fall risk. In addition, Dionyssiotis states that impaired mobility may lead to decreased ability to ‘break’ ones fall, resulting in harder impacts which are more likely to result in serious injuries such as fractures. General Overview Of Gait Disorders